Tensioner



FIG. 1 is a top-front-left perspective view of a tensioner according to the claimed design.

FIG. 2 is a rear-bottom-right perspective view thereof.

FIG. 3 is a front view thereof.

FIG. 4 is a rear view thereof.

FIG. 5 is a left side view thereof.

FIG. 6 is a right side view thereof.

FIG. 7 is a top view thereof; and,

FIG. 8 is a bottom view thereof.

The broken lines in the drawings illustrate portions of the tensioner that form no part of the claimed design. 

CLAIM The ornamental design for a tensioner, as shown and described. 